This chapter focuses on Propositional Logic, the most elementary part of mathematical logic. The standard truth-functional connectives and, or, not, if-then, and if and only if are systematically introduced; a natural deduction system of inference rules for these connectives is given; and mathematical proof strategies associated with these rules are explored. This material is extended in Chapter 2 to First-Order Logic. Together these chapters provide a sound basis for learning how to read and write deductive arguments in mathematics and elsewhere. It thus undergirds later discussions of discrete mathematical topics, where such arguments are central. Chapter 1 also provides a content basis for Chapter 7, which looks at how Boolean logic is realized using logic gates.